Computer-aided design (CAD) systems have become an important design tool used by designers, engineers and architects to build graphical models and drawings that simulate practical mechanical, electrical and architectural components for various applications. An advancement and replacement to the traditional hand-drawn process, a CAD system provides interfacing modules for creating graphical objects while delivering precise and accurate measurement and dimensions of these objects to users. With appropriate data entered into interfacing modules, a CAD system can further provide efficient product realization and visualization, structural analysis, and manufacturing development.
During a design stage, numbering graphical objects is sometimes necessary. Conventionally, to establish a sequence among a group of objects, a user manually assigns an identifier (e.g., numeric, alpha-numeric, etc.) in the form of text to each object. An example of using this technique includes numbering rooms or floors of a building.
However, conventional CAD systems often lack numbering control and management, and renumbering multiple objects is often inevitable when the sequence is interrupted. From a user's perspective, renumbering objects can be a time consuming and tedious operation. For example, if a hotel room in a CAD model representing a hotel floor is erroneously assigned with an inaccurate room number, a user endures the labor-intensive challenge of manually reassigning the room with a correct room number, as well reassigning room numbers to multiple other rooms on the same floor, so as to restore a specific sequence. The tediousness of the task further magnifies the possibility of incurring inadvertent errors, and potentially causing significant problems during actual implementation of the design represented by the CAD model.